Provided by Oregon State University
Recently, scientists at Oregon State University in the United States published a paper in the journal Cretaceous Research that said they found a 100 million-year-old weevil that is different from any known fossil or extant weevil. The amber-wrapped male specimen represents a new species, Rhamphohorus legalovii. George Poinar Jr., the author of the paper, refers to it as the "mammoth weevil" because it has a huge beak that looks like the mammoth's large nose. Because the fossil is so exotic, entomologists will continue to discuss its place in the evolutionary system for years to come.
The weevil is a small herbivorous beetle known for its slender nose, and there are nearly 100,000 species of weevils known today. Weevils with right-tentacles are classified as primitive weevils, while those with elbow-like curved antennae are considered true weevils. Rhamphohorus is a primitive weevil with 11 antennae, which Poinar classifies as a pineflower weevil. "The ancient history of this family is told by species in amber, and there are no known extinct or extant species with this slender beak," he said. "
The newly identified weevils belong to the Subfamily Cimberidinae, and the weevils in the subfamily all have long beaks. Of the seventy known Cimberidinae species, many are type ii in sex, with males and females looking very different. As a result, the female mammoth weevil may have a much shorter beak.
Compared with trees, the new species are more likely to live on the ground, with a body length of 5.5 mm, almost half of which is the head and beak. Poinar said: "Rhamphohorus's mid-foot is extended, which may have enhanced its ability to grasp the surface of the plant or allowed it to better approach enemies when competing for a mate." The injuries to Rhamphohorus' body suggest that it may have fallen into the resin while competing with another weevil for a mate and has been preserved to this day. "
Poinar said: "Rhamphohorus exhibits features that many extant or extinct weevil fossils do not have. Lifestyle and microhabitating together influenced the evolutionary development of this weevil, which gave us a deeper understanding of the morphological diversity of the weevil in the middle Cretaceous. "
Editor: Hua Hua Reviewer: Seamus Editor:Chen Zhihan
Journal Source: Cretaceous Studies
Issue No. 0195-6671
Original link: https://phys.org/news/2021-07-ancient-newly-mammoth-weevil-huge.html
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